The War Between Universes - Percy Jackson Multi-Fandom Story
by Aelin-Annabeth1682
Summary: A war is brewing between this Universe and another. Chaos sends Percy Jackson to different worlds so that he can make allies to fight in the raging war. If he dose not succeed he will never go home and all will be lost. A multi-fandom story created by both @WeirdReader06 and myself. Updates slow.
1. Prologue

Percy Jackson sat on the beach with his feet in the cool, water. It was months after the Giant War, it was nice to relax without having to worry about a threat to defeat or a quest to accomplish.

He shifted his gaze from the ocean, to the girl sitting beside him. Her blonde curls hitting her back, her stormy grey eyes staring at the sea. Their heads snap behind them to a loud noise coming from far away, towards the back of the camp. They jump to their feet and rush over to see what was happening. A girl of 16 was standing at the camp border, golden dust covering her body from head to toe.

Her blue eyes had confidence and triumphant behind them as she scans the camp that lays before her. Percy and Annabeth run up to her as she staggers slightly to the side. Percy and Annabeth came up to the side of her and they could see how hard she was trying to stay on her feet. Blood dripped down the side of her face, making a clean pathway through the golden dust. Annabeth gently touched the girl's arm and gripped it as gentle as she could so the girl wouldn't fall. The girl's eyes dropped and she staggered backward but luckily Percy caught her before she could hit the ground.

Annabeth and Percy were both thinking the same thing, "Who is she?"


	2. Chapter 1

They brought the girl to the infirmary where Will, a son of a Apollo, told them her injuries. "She has a sprained hand and a broken rip." he told them. "Who even is she?" Percy questioned, but Will shook his head and said, "Ask her when she wakes up."

The girl didn't wake up until around afternoon the next day, Percy and Annabeth visited her to ask questions. They walked in to the girl slumped against her pillow drinking Nectar. She had a wrap around her stomach and a band aid across her nose. Percy and Annabeth sat down on chairs next to the bed, "Hi, my name is Percy and this is Annabeth." Percy said waving at the girl. The girl looked at them through her dirty blonde hair, "Hello, i'm Elizabeth."

Annabeth smiled at Elizabeth, "What happened on the border?" Elizabeth frowned, "My mom told me about this camp before she died, after she died my home became unbearable so I ran when I was eight. I've been looking for this camp for years! I came up the hill when a creature came at me." she shuddered, "It was big,scary and had one eye, it ran at me waving a club. I don't exactly know how but suddenly I had a spear. I had no idea what I was doing, I stabbed it a few times and it exploded into this golden dust. I-I, how did I get here?"

"I carried you after you blacked out." said Percy. He had this calming, peaceful aura around him that made Elizabeth feel relaxed, feel like she can trust him with her life. "What is this stuff?" She asks, while drinking the golden Nectar. "Nectar, it helps heal you faster." Annabeth replies.

"It tastes like my mum's chocolate milk she would make me." Elizabeth said. She takes another sip of the drink, letting it warm her throat and fill her mouth with a delicious taste. The more she drank, the more she felt her bones mend together. The pain go away. In a matter of minutes she was able to move without a shooting pain, cascading up her torso. Elizabeth was about to attempt to stand, when a gentle hand pushes her back down.

"I'm not letting you get up for another hour or so." Will declares. Elizabeth grunts before lying back down on the bed, the soft fabric of the blanket warm on her tanned skin. She blows a strand of hair off of her face, glaring at Will. 'Why can't she get up?'

Percy looks at the girl in the bed. Not just any bed, the same one were he met Annabeth for the first time when they were twelve. So young and innocent. Elizabeth starts to tap her fingers in boredom. "I'm hungry. I want food." she said with a slight pout. Will looks at Annabeth and Percy, "Get her some food I guess." Percy nodded and went off towards the Pavilion. Annabeth looked at Elizabeth, "How long have you stayed alive?" It was kind of impressive an eight year old could survive for so long. Elizabeth shrugged, "I'm not really sure. Years pass, and I don't keep track. I think around 16?" Annabeth nodded, "You look around 16."

Right as Elizabeth opened her mouth to say something else Percy returned carrying a plate of hot food. Elizabeth looked at the food with hunger and lust, as Percy walked beside the bed she jumped up slightly and grabbed the plate. Annabeth and Percy looked at her with raised eyebrows, "Sorry, the last time I ate a real meal was last, last Monday." Percy looks at Annabeth asking a silent question. 'How could she not eat for three weeks and not be dead?' Annabeth looks back at Percy with a silent reply. 'I don't know but this girl, there is something different about her. I can feel it.'


	3. Chapter 2

Elizabeth fitted right in with the campers, she was nice and threw in a lot of sarcastic comments here and there. She sadly though was undetermined, a lot of the campers liked to guess who her godly parent was. She was good at mostly everything except arts (Drawing and weaving), and fit some traits from each god. The campers (the Stolls) decided to create a betting system on who her godly parent was.

A week had passed and she still hasn't been claimed. Bids have been raised, and arguments have come and gone. Annabeth suspects that by the end of tonight, after capture the flag she will be claimed. Elizabeth isn't sure about it, but no one knows what could happen.

-food break-

The horn blasted signalling the start of the game. Athena, Poseidon, Hephaestus, Apollo and Dionysus on the blue team and Ares, Hermes, Demeter, and Aphrodite on the Red team. Both teams charged, armour clattering, swords waving, shields held high. Elizabeth on the red team was charged with border patrol. 'A boring waste of time', she thinks.

Percy slashed through the reds like butter. He moved through their ranks with ease and was able to grab their flag. Annabeth behind him, as he races for the border. He spots Elizabeth in the corner of his eyes being hassled by members of Dionysus's cabin. Even though they are on his side, his fatal flaw of loyalty kicked in and he handed the flag to Annabeth before sprinting over to Elizabeth.

"Stop hurting her, the games over." said Percy, glaring at the teenagers. Another horn blasts into his ears, the end of the game. The Dionysus kids snicker before walking off.

"Thanks," Elizabeth tells him.

"No problem." He replies. "Come on, dinner is about to start." Percy leads Elizabeth to the dining Pavilion. A cold hard hand grabs his wrist. Percy whirls around and see Elizabeth staring into his eyes.

"I'm sorry." said Elizabeth. He barely have time to react to her foot sliding underneath him, tripping him over, knocking him out cold. Percy's body is lifted into the air.

Percy slowly opened his eyes, feeling slightly sore. He slowly remembered what happened, he and Elizabeth were walking towards the dining Pavilion when she knocked him out. He looked around but saw nothing but black, "What is this place?" he said out loud.

"Nothing." a voice said behind him, Percy stood up and turned around to see Elizabeth standing there with her hands behind her back.

"Why would you bring me here?" he questioned.

"Because he commanded it." she said with a blank face.

"Who?" Percy asked, Elizabeth smirked.

"You ask questions you think I'm going to answer."

Percy frowned, "Okay then when will he be here, who ever he is."

Elizabeth smiled, "Oh don't worry, he likes his dramatic entrances."

Percy blinked, "Dramatic entrances, who is he? Zeus?"

Elizabeth rolled her eyes, "No you idiot, Zeus is nothing compared to my father."

Percy frowned, "Your father? How do you know who he is?"

Elizabeth rolled her eyes again, "You really are a Seaweed Brain."

Percy blinked, "What?"

Elizabeth rolled her eyes yet again and said nothing. Instead she looked down at the dark ground and tapped her foot. 'How could one be this stupid?' She asks herself. Elizabeth stands there and waits for her father.

Dark smoke floods into the room, extinguishing all light. The ground shook, and in a flash of light the hole room changed from a dark cavern to a grand throne room. On top of the black ivory throne sat a man wearing all black, with black hair and silver eyes to match his thin cloak, staring at Percy. His eyes avert to his daughter before going back to the boy. "Well done my daughter, you succeeded."

Elizabeth smirked, "It was easy."


	4. Chapter 3

"The universe is in danger." Chaos's voice rumbles through the room, "and you are going to help save it." He takes a quick pause to breath. "I want you to go around the universe and convince some warriors to help fight in a war between this universe and the one known as Opeon, if we do not win all that you see before you will be burned to ash, and if we win, peace and prosperity will forever rage."

"What if I say no?" Percy asks.

"Than we will wait here for however long it takes you to say yes. The conditions of you doing this goes like this. Everytime you convince one group a portal will open for you to go to the next group of people. Once you have finished the last portal will take you to your home planet and you will not have to fight in the war if you do not wish to. If you fail to convince someone, than you will be stuck on that planet or place until you die or somehow manage to make them fight."

Percy realises that he has no other choice. "I will do it." He says, so that one day he will see Annabeth again.

"Good, now sign these contracts, and you will be of for your first adventure." Elizabeth handed him some papers and a pen. "Oh and Elizabeth will be joining you to make sure you don't kill yourself in some stupid way." Why does everyone think he is some Kelp Head?

Percy turns down Elizabeth's offer of a pen, saying he already has one and un-caps Riptide. In doing this he almost stabs Elizabeth in the stomach making Elizabeth glare at him, before placing the cap on the hilt of the sword to turn it into a pen. The ink comes out glowing, bronze as Percy rights down his name, not bothering to read the contract.

"Thank you for your corporation." Chaos says, he than waves his hand sending both Elizabeth and Percy through a portal.

Percy gasps as his eyes set upon a large, stone castle towering over a lake. "Dam, this is Harry Potter!" he squeals.

Elizabeth nodded, "Of course. Think of their spells, they would be perfect allies for the war. Also did you just squeal?"

Percy's eyes widen,"...No"

Elizabeth raised an eyebrow, "Uh huh." She looked toward the castle, "Shit, it's bigger in person." She looked around where they were, "It appears we are in Hogsmeade. And no we are not going to The Three Broomsticks." She added as Percy opened his mouth.

Percy pouted, "But whyyyyyyy?"

Elizabeth shook her head, "You demigods." she muttered before speaking louder, "Because we're here for a reason. Convincing wizards and witches to help with the war." Percy still pouted, "Besides it's extremely early."

Percy huffed, "Fine..."

Elizabeth nodded, "Perhaps we should go to Hogwarts? McGonagall is Headmistress-" she was cut off by Percy frowning.

"Poor Dumbles." Elizabeth shook her head before continuing, "So maybe we should try talking to her first."

Percy frowns, "Wait...so we aren't going to meet Harry Potter?" Elizabeth looks at him in disapproval.

"No, we are not."

Percy shouts at Elizabeth. "But, he is the most amazing person ever! And we came all this way, I must see him. He is my idol!"

Elizabeth roles her eyes. "Before you start wetting your pants in excitement, we got to go speak to McGonagall." Percy glares at her and starts to skip towards Hogwarts. Singing ,'I'm going to Hogwarts.' over and over again.

Elizabeth rolled her eyes and followed him slowly, "Am I in hell?" she thought. She caught up with Percy and he asked, "Hey so all that stuff-" he didn't finish that sentence as he faltered, Elizabeth has had a cool expression all this time but she looked at the ground sadly.

"Fake? No well the backstory and that. But the friendships I have with everyone, that was real." Percy nodded and they continued to Hogwarts in a comfortable silence.

They arrived at the giant, wooden doors in front of the castle.


	5. Chapter 4

It took all of Percy's and Elizabeth's strength to open the doors to the castle. Their footsteps echoed through the large hallways. "Who else do you think is here?" Percy asked, Elizabeth shrugged.

"Most of the teachers maybe? But it's okay if anyone comes near us I'll just make us invisible." She said looking around as they walked.

Percy looked at her with wide eyes, "You can do that?"

Elizabeth nodded as they made their way to the Headmistresses' office, "My father if Chaos creator of the universe so I can do a lot of things."

"Where is the Headmistresses' Office?" Elizabeth asks.

"Through this corridor, than a left, straight, another left than a right. You will see a Gargoyle and that is the entrance." Percy said, excitement lacing his words.

"How many times did you watch the movie?" Elizabeth questions.

"14 each."

Elizabeth's eyes widen. "Shit that's a lot." They turn a corner and see Professor Slughorn standing with Hagrid talking about something.

"Oh my gods. That's Professor Slughorn and Hagrid!" Percy squeals like a fan girl. Elizabeth quickly grabs Percy's hand to turn them transparent. Both the teachers heads snap towards them, only to see an empty corridor.

Elizabeth guides Percy around them and they continue their mission towards the Gargoyle. They reach it after a few awkward minutes of Elizabeth holding Percy's hand. She lets go and wipes the sweat off, that was disgusting.

"We need a password." Percy said.

"Of course we do." She replies. "Any idea on what it is?" Percy thinks for a moment.

"Lets try...Dumbledore." Percy was right and the gargoyle swept to the side revealing a circular stairwell. "This is so cool." Percy mutters before stepping onto the stairs.

A big brass knocker lays before them, Percy lifts his hand and knocks. "Come in," A feline voice rings out. I look at Percy before opening the door. I see a middle aged women dressed in green, with grey/brown hair and witches hat upon her head.

"Who are you, and how may I help?" She asks inspecting the children.

"Umm...hey I am Elizabeth. This is Percy, we are wondering if we could ask a few questions?." She said.

"Sure, take a seat." The Professor said. "What's the question?"

"Will you be willing to fight in a war again?" The Professor looked a bit shocked. Elizabeth realises that she was probably a bit forward so she starts to explain the whole thing to McGonagall. In a matter of moments McGonagall's face changes from relaxed to wide-eyed.


	6. Chapter 5

"I don't know if I can condom the students into doing all lost someone, someone close to them. To put them through that pain again will be astronomical, but if we do not help they may die anyway. Do you see the problems you have pressed upon me, Percy and Elizabeth?" McGonagall analyses. Percy nods at her and then opens his mouth to speak.

"Yes I do. Except this way if you fight you have a reason to, something to fight for. Sometimes that is all you need in order to get through a fight and win the war." Percy says with confidence laced through his voice.

McGonagall contemplates it for a second. "I will have to speak with the other teachers and then to the students before I decide on what to do. In the meantime, would you like to stay in Hogsmeade until I give you an answer?" she questions.

"That would be great, thank you." Elizabeth says kindly. Percy looks at her in shock, he never knew she could be kind, this needs to be recorded in some kind of extremely rare events book.

McGonagall smiles, "Do you know the way?" She says uncertain.

"Yes, we do. Thank you for your time," Percy says and turns around. He walks out of the massive office, Elizabeth following behind him.

McGonagall watches the two leave. She shakes her head not knowing what to do, but in her heart she knows that fighting is the only option. Fighting is the key to never ending peace.

-line break-

Elizabeth groans and lies down on her bed. "I can't believe I have to share a room with you," she says grumbling.

"Hey! It's not my fault they only had one room available," Percy says in protest. Elizabeth rolls her eyes and Percy glares at her.

"I just want to go to sleep. Don't wake me up tomorrow, I don't do mornings very well," she warns. Elizabeth pulls the sheets of her bed over her body and rolls to the side so her back is facing Percy.

"You're such a kind friend," Percy says acting hurt.

"I'm not your friend, just your business partner. Now let me sleep," Elizabeth replies.

Percy scowls then gets into his bed on the other side of the room. His eyes close and he quickly falls into a deep slumber, Elizabeth following afterwards.


	7. Chapter 6

The bright rays of sunlight shined into Percy's and Elizabeth's room. Sea-green eyes fluttered open, a groan echoed through the room.

"About time sleepy head," a voice rang out into the room. Percy sat up and blinked a few times, adjusting his vision.

"What's the time," he asked the girl standing a few meters away from him.

"Seven," Elizabeth replies blankly.

"Then why am I awake?" Percy asked.

"Cause I opened the blinds," Elizabeth said obviously.

"Why?" Percy questioned.

"We have a job to do. You know, the whole saving the universe thing. Also, there's a whole heap of wizards and witches outside, they were going to wake you up anyway," Elizabeth walks over to the other side of the listens for a moment, and sure enough sounds of children were heard outside the door. Elizabeth opens the door, "get dressed, meet me outside."

"Wait," Percy called.

"What?" Elizabeth said annoyed.

"Can I call you Liz?" He asked. Elizabeth sighed and walked out.

"I guess that's a yes," Percy called after her. To his dismay, there was no reply. He listened for a bit longer to hear nothing, there was just silence.

Then there was a scream.


End file.
